The Castello Aragonese is easily the most impressive historical monument in Ischia. It stands on a volcanic rock connected to the island by a bridge built in 1438 by Alfonso of Aragon. The Castle, overlooking the vast horizon of the sea, was originally built as a castrum in 474 BC by Gerone of Siracusa and, after a long period of abandonment, reached its golden period during the fourteenth century.

Under the Aragonese dynasty, it became a political, cultural and spiritual centre of notable interest. The Renaissance court of the noble poet Vittoria Colonna, saw the peak of the castle's splendour. Her court raised the Castello to heights of unheard glory: it breathed new life into the place; the arts and sciences flourished as never before under these skies - even Michelangelo was enticed here - but the decline had already begun in the 15th century and continued for more than 100 years.